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    <title>Document</title>
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    <script>
        /***
         *  = 
         *  +=
         *  -=
         *  *=
         *  /=
         *  %=
         */
        var a = 1;

        a += 2; // a = a + 2;

        a -= 10; // a = a - 10;

        a *= 4; // a = a * 4;

        a /= 2; // a = a / 2;

        a %= 10; // a = a % 10;

        console.log(a);



    </script>
</body>
</html>